The ASP. NET Web API implements caching through Actionfilter

1 usingSystem;2 usingSystem.Collections.Generic;3 usingSystem.Linq;4 usingSystem.Threading;5 usingSystem.Threading.Tasks;6 usingsystem.web;7 usingSystem.Web.Caching;8 usingSystem.Web.Http;9 usingSystem.Web.Http.Controllers;Ten usingSystem.Web.Http.Filters; One  A namespaceWebApi - { -[AttributeUsage (AttributeTargets.Class |AttributeTargets.Method)] the      Public classCacheattribute:actionfilterattribute -     { -          Public stringabsoluteexpiration {Get;Set; } -          Public stringslidingexpiration {Get;Set; } +          PublicCacheItemPriority Priority {Get;Set; } -  +          PublicCacheattribute () A         { atPriority =Cacheitempriority.normal; -         } -  -          Public Override voidonactionexecuting (httpactioncontext actioncontext) -         { -             varActiondescriptor = Actioncontext.actiondescriptor asReflectedhttpactiondescriptor; in             if(NULL==actiondescriptor) -             { to                 Base. OnActionExecuting (actioncontext); +             } -             varKey =NewCacheKey (Actiondescriptor.methodinfo, actioncontext.actionarguments); the             varArray = HttpRuntime.Cache.Get (key. ToString ()) as Object[]; *             if(NULL==Array) $             {Panax Notoginseng                 Base. OnActionExecuting (actioncontext); -                 return; the             } +             varValue = array. Any ()? array[0] :NULL; A             varActionResult = value asIhttpactionresult; the             if(NULL!=ActionResult) +             { -Actioncontext.response =Actionresult.executeasync (Cancellationtoken.none). Result; $                 return; $             } -Actioncontext.response =ActionDescriptor.ResultConverter.Convert (actioncontext.controllercontext, value); -         } the     } - Wuyi      Public classCacheableactiondescriptor:reflectedhttpactiondescriptor the     { -         PrivateCacheattribute Cacheattribute {Get; } Wu  -          PublicCacheableactiondescriptor (Reflectedhttpactiondescriptor actiondescriptor, Cacheattribute CacheAttribute):Base(Actiondescriptor.controllerdescriptor, Actiondescriptor.methodinfo) About         { $Cacheattribute =Cacheattribute; -         } -  -          Public Overridetask<Object> Executeasync (httpcontrollercontext controllercontext, idictionary<string,Object>arguments, CancellationToken cancellationtoken) A         {   +             varabsoluteexpiration =cache.noabsoluteexpiration; the             varslidingexpiration =cache.noslidingexpiration; -             varPriority =cacheattribute.priority; $             if(!string. Isnullorwhitespace (cacheattribute.absoluteexpiration)) the             { theabsoluteexpiration = DateTime.Now +Timespan.parse (cacheattribute.absoluteexpiration); the             } the             if(!string. Isnullorwhitespace (cacheattribute.slidingexpiration)) -             { inslidingexpiration =Timespan.parse (cacheattribute.slidingexpiration); the             } the             varCacheKey =NewCacheKey (MethodInfo, arguments); About             varresult =Base. Executeasync (ControllerContext, arguments, CancellationToken). Result; theHttpRuntime.Cache.Insert (Cachekey.tostring (),New[] {result},NULL, absoluteexpiration, slidingexpiration, priority,NULL); the             returnTask.fromresult (result); the         } +     } -  the      Public classCacheableactionselector:apicontrolleractionselectorBayi     { the          Public Overridehttpactiondescriptor selectaction (httpcontrollercontext controllercontext) the         { -             varActiondescriptor =Base. SelectAction (controllercontext); -             varReflectedactiondescriptor = Actiondescriptor asReflectedhttpactiondescriptor; the             if(NULL==reflectedactiondescriptor) the             { the                 returnActiondescriptor; the             } -             varCacheattribute = Reflectedactiondescriptor.getcustomattributes<cacheattribute> (). FirstOrDefault ()?? theReflectedactiondescriptor.controllerdescriptor.getcustomattributes<cacheattribute>(). FirstOrDefault (); the             if(NULL==Cacheattribute) the             {94                 returnActiondescriptor; the             } the             return NewCacheableactiondescriptor (Reflectedactiondescriptor, cacheattribute); the         }98     } About}

Register Actionselector

1 usingSystem;2 usingsystem.web;3 usingSystem.Web.Http;4 usingSystem.Web.Http.Controllers;5 usingWebApi;6 7 namespacewebhost8 {9      Public classglobal:httpapplicationTen     { One         protected voidApplication_Start (Objectsender, EventArgs e) A         { -             //registering the ASP. NET Web API Route -GlobalConfiguration.Configuration.Routes.MapHttpRoute ("default","Api/{controller}/{id}",New{id =routeparameter.optional}); the  -  -             //Register Cacheableactionselector -GlobalConfiguration.Configuration.Services.Replace (typeof(Ihttpactionselector),Newcacheableactionselector ()); +         } -     } +}

Using Cacheattribute

1      Public classDemocontroller:apicontroller2     {3[Cache (absoluteexpiration ="00:00:02", slidingexpiration ="", priority =Cacheitempriority.high)]4          PublicDateTime Get ()5         {6             returnDateTime.Now;7         }8}

The ASP. NET Web API implements caching through Actionfilter